Pressure ventilating unit



Aug. 4:, 1942.

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1942- c. o. BERGSTROM 2,292,192

PRESSURE VENTILATING UNIT Filed Sept. 8, 1939 2 Sheets-Sheet 2 H (7. 3 IIQ 1 l x V I9 Patented Aug. 4, 1942 PRESSURE VENTILATING UNIT Carl 0.Bergstrom, Boston, Mass, assignor to B. F. Sturtevant Company, Boston,Mass.

Application September 8, 1939, Serial No. 293,941

4 Claims.

This invention relates to ventilating units and relates moreparticularly to pressure ventilating units for railway passenger cars.

Pressure ventilating systems utilizing relatively large volumes ofoutdoor air have been successfully used in many railway passenger carsfor cooling the passenger space. Their cost is relatively low ascompared to air conditioning systems and they have been found effectivesubstitutes for the latter.

The successful pressure ventilating systems which have been usedheretofore, have been similar to these disclosed in the U. 8. Patent No.2,142,842, which issued January 3, 1939, on an application of M. E.Hanson, and in my copending application, Serial No. 220,681, filed July22, 1938. In such systems, the centrifugal fans used have been the onlystock items used, the ducts and littings being constructed on the jobsat the time of installation. It has been necessary not only to use airduets with such systems, but to cut holes in the car ceiling for thefans and in the sides of the car for the air inlets. As a result, thecost of the equipment used with the fans has greatly exceeded the costof the fans.

This invention provides a package unit ventilator for the pressureventilation of railway passenger cars, which may be assembled at thefactory complete with filters and auxiliary equipment and which may bemounted as one of the several units from the roof of the car. No ductsare necessary and the only alteration of the car is the provision of airinlets. As a result, the cost of the necessary equipment and of itsinstallation has been greatly reduced.

An object of the invention is to reduce the cost of pressure ventilatingsystems for railway passenger cars.

Another object of the invention is to provide a self contained pressureventilating unit for a railway passenger car.

Other objects of the invention will be apparent from the followingdescription taken with the drawings.

The invention will now be described with reference to the drawings, ofwhich:

Fig. 1 is a plan view looking downwardly upon one of the pressureventilating units embodying this invention, installed in a railwaypassenger car;

Fig. 2 is an elevation View, of the interior of a car equipped with theunit of Fig. 1 with the roof and floor of the car in section;

Fig. 3 is an enlarged sectional view along the lines 3-3 of Fig. l, and

Fig. 4 is an enlarged sectional view along the lines 44 of Fig. 1.

The unit consists of the centrifugal fan 5 with motor 6, the sheetmetal, upper wall I, the sheet metal converging side walls 8 and 9, thevertical, sheet metal, side walls IS, the horizontal lower wall I8, therecirculated air inlet I0, and the filters II. These are all assembledas a unit at the factory.

For installation, it is only necessary to provide the outdoor air inletsI2, for each unit, in the roof of the car, and to mount the hoods I3 onthe roof of the car above the inlets.

The walls 8 and 9 not only support the assembly from the roof of thecar, but provide air guiding passages for directing the air into theinlet of the fan 5. V

The fan 5 is preferably similar to that disclosed in my Patent No.2,142,834, which issued January 3, 1939, and the patent discloses all ofthe details of the embodiment of the fan illustrated herein.

The horizontal lower wall I8 contains a central, circular aperturethrough which the lower portion of the fan rotor 22 extends below thewall I8 and through which the upper portion of the rotor 22 of the fanextends above the wall I8. The fan 5 is supported around the aperturefrom the wall I8. The wall I8 is supported by the lower ends of the sidewalls 8.

The recirculated air inlet It! in the side wall 9 contains the dampersI4 which may be adjusted by the handle 5 to control the amount ofrecirculated air admitted to the inlet of the fan. A similarrecirculated air inlet could be provided in the opposite wall 8 ifdesired. It is not eX- pected that the recirculated air inlets will beused during the cooling season and they may be omitted as far as coolingis concerned. The same equipment will be used during the heating season,at which time the recirculated air inlets may be desirable.

The upper filter supports I9 are attached to the upper wall I of thunit, above the fan 5 and midway between the air inlet openings I2. Thelower filter supports 20 are attached at their outer sides to the lowerends of the side walls 8 and at their inner sides to the bottom wall I8and serve to support the wall I8 from the walls 8. The upper ends of theside walls 8 are attached to the ceiling of the car adjacent the outeredges of the air inlet openings I2.

The filter supports I9 and 20 are so placed-with respect to the sidewalls 8 and to each other, and the side walls 8 are so placed withrespect to the air inlet openings l2 that the side walls 8 form theouter edges of a W-shaped outline and that the filters II, in thesupports I9 and 20, form the inner legs of the W-shaped outline. Theinlets I2 are between the inner and outer legs, and the converging sidewalls 8 forming the outer legs of the outline, form air guiding passagescausing the air from the inlets 2 to flow through the filters l I intothe inlet of the fan 5.

The filters H are mounted along converging lines for conserving spaceand may be withdrawn, as illustrated by the dotted lines of Fig. 3,through the doors 11 arranged between th fan 5 and the lower end of thewall 8 on one side, and the lower end of the wall 9 on the other side.

A railway car to be pressure ventilated will have several of theventilator units embodying this invention spaced along the longitudinalcenter of the car, and bolted to its roof, the fans collectively drawingin about 4800 cubic feet per minute of outdoor air and discharging itinto the passenger space.

While one embodiment of the invention has been described for the purposeof illustration, it should be understood that the invention is notlimited to the exact apparatus and arrangement of apparatus described,as departures therefrom may be suggested by those skilled in the art,without departure from the essence of the invention.

What is claimed is:

1. A pressure ventilating unit for a railway passenger car, comprising acasing having side walls with their upper ends adapted for attachment tothe roof of said car, and having a lower wall with a central opening, acentrifugal fan supported around said opening by said lower wall andhaving its rotor extending from a point above to a point below saidlower wall, lower filter supports attached at their inner sides toopposite ends of said lower wall and attached at their outer sides tosaid side walls, said supports serving to support said lower wall andfan from said side walls, and upper filter supports, said supportscontaining filters forming an inverted V-shaped outline above said fan,said side walls converging towards said lower supports and forming withsaid filters a W-shaped outline.

2. A pressure ventilating unit for a railway passenger car, comprising acasing having side walls with their upper ends adapted for attachment tothe roof of said car, and having a lower wall with a central opening, acentrifugal fan supported around said opening by said lower wall andhaving its rotor extending from a point above to a point below saidlower wall, filter supports attached at their inner sides to'oppositeends of said lower wall and attached at their outer sides to said sidewalls, said supports serving to support said lower wall and fan fromsaid side walls, and doors in said supports for providing access to thefilters therein.

3. A pressure ventilating unit for a railway passenger car, comprising acasing having side walls with their upper ends adapted for attachment tothe roof of said car, and having a lower wall with a central opening, acentrifugal fan supported around said opening by said lower wall andhaving its rotor extending from a point above to a point below saidlower wall, lower filter supports attached at their inner sides toopposite ends of said lower wall and attached at their outer sides tosaid side walls, said supports serving to support said lower wall andfan from said side walls, and upper filter supports, said supportscontaining filters forming an inverted V-shaped outline above said fan,said side walls converging towards said lower supports and forming withsaid filters a W-shaped outline, said casing having air inlet openings,one above each of said filters.

4. In combination a railway passenger car and a pressure ventilatingunit, comprising a casing having side walls having their upper endsattached to the roof of said car, and having a lower wall with a centralopening, attached to said side walls, a centrifugal fan supported aroundsaid opening by said lower wall and extending through said opening froma point above to a point below said lower wall, said side wallsconverging towards said lower wall, filters in said casing supportedalong lines diverging towards said lower wall and forming with said sidewalls a W-shaped outline, and air inlet openings in said roof betweensaid side walls and said filters.

CARL 0. BERGSTROM.

